The Israeli officials who hacked into Kaspersky's network over two years ago then warned their United States counterparts of the Russian intrusion, said the New York Times, which first reported the story.

It is as yet unclear on whether Kaspersky was involved in aiding the Russian hackers, or if the hackers simply used Kaspersky's software as a backdoor onto computers worldwide that use the anti-virus.

Following the discovery, several government agencies, including the Federal Bureau of Investigation (FBI) and Homeland Security, ordered the removal of all Kaspersky software from government devices, while the FBI also recommended private users to stop using the software too.

It is not yet publicly known what other US secrets the Russian hackers may have discovered by turning the Kaspersky software into a sort of Google search for sensitive information, the Times said.

Eugene Kaspersky, a businessman and former Russian Defense Ministry official, founded Kaspersky Lab in 1997.

Meanwhile, Kaspersky Lab insists that it doesn't help the Russian government to spy on other countries. And given such Russian hacking operation were discovered some time ago, there's a chance that Kaspersky may have patched a backdoor, if it indeed existed, as part of its regular software updates. It said it was anxious that the Russian government had possibly compromised the firm.

"The BSI has no evidence for misconduct by the company or weaknesses in its software", the German intelligence agency said in an emailed statement to Reuters.

Even in this case, they offered no evidence that the Russian government was specifically targeting the USA, nor that Kaspersky knew about the intrusion.

Kaspersky first noticed intrusion by Israel referenced in The New York Times story back in 2015, when it reported that "a sophisticated cyberespionage actor" had infiltrated its systems using code that resembled a previous attack.

"Kaspersky Lab reiterates its willingness to work alongside US authorities to address any concerns they may have about its products as well as its systems, and respectfully requests any relevant, verifiable information that would help the company in its own investigation to certifiably refute the false accusations".

The company "does not possess any knowledge" of Israel's hack, the Post cited the statement as saying.

US intelligence agencies have concluded that Russian President Vladimir Putin ordered a multipronged digital influence operation previous year in an attempt to help Donald Trump win the White House, a charge Moscow denies.